This invention relates to an optical image generator having a spatial light modulator and a display device so that an image pattern created by computer and displayed on the display device in a two-dimensional manner can be used to perform parallel processing of optical information.
A spatial light modulator consists of an electron beam source and an electrooptic crystal wherein the image of electrons emitted from the electron beam source can be stored and may be changed corresponding to the optical image change. It can be used as a transducer for incoherent to coherent light conversion. It can also be used in pre-processing to determine the threshold level of data which are being input, to perform logic operations with regard to data which are being input, and to determine the contour of the optical image.
A spatial light modulator can be accessed either by means of the optical address method, whereby two-dimensional image signals can directly be written into the material, or by means of the electrically addressing method, whereby time-sequential electric signals can be written into the material.
The optical address method is used in a spatial light modulator wherein the photocathode constitutes the electron beam source, and the electrically addressing method is used in another type of spatial light modulator wherein an electron gun constitutes the electron beam source.
A spatial light modulator of the electrically addressing type, with an electron gun constituting the electron beam source, requires a set of electron lenses or electromagnetic coils for use in both focusing and deflecting the electron beam from the electron gun.
If this type of spatial light modulator is connected to a computer so as to write two-dimensional image signals calculated by computer into the spatial light modulator, the interface between the spatial light modulator and the computer may be complicated.